Police are searching for men, who knocked down and beat the leader of Bremen's branch of the conservative Alternative for Germany, lawmaker Frank Magnitz, following a recent string of attacks against his party in the Eastern state of Saxony, including a blast outside their office in Doebeln last week.
Mr Magnitz, 66, had just left a new year reception in Bremen's Kunsthalle art museum when he was attacked in the city's Goetheplatz as he walked to a central vehicle park.
"This is the result of the ostracism and agitation AfD faces", he said, suggesting other German political parties were partly responsible for the attack because they had compared AfD to Adolf Hitler's Nazi party because of its nationalist rhetoric and campaigns against migrants.
Bremen, Germany's smallest state, holds a regional election on May 26, the same day as European Parliament elections in which AfD hopes to make gains.
Leading politicians across the political spectrum in Germany condemned the attack Tuesday.
Magnitz was beaten in an"assassination attempt" according to his party
A far-right chairman of a German anti-immigrant party was nearly beaten to death in a "politically motivated assassination attempt". "Hopefully, the police will be able to quickly catch the perpetrators".
An explosive device detonated in a bin and damaged an AfD office in Saxon, last week.
Foreign Minister Heiko Maas said there was "absolutely no justification" for the use of violence despite political differences. "Anyone who fights hatred with hatred always lets hatred win in the end", he wrote on Twitter. It entered the national parliament in 2017 and is now the biggest opposition party there.
Authorities have yet to determine the motives behind the attack, but with its growing popularity, the opposition AfD party has become a target of increasing criticism and attacks over its anti-immigration and other ultraconservative policies.
AfD entered the national parliament (Bundestag) for the first time a year ago with 94 seats and now has representatives in every German state parliament. The attackers fled the scene after beating the politician unconscious, according to Germany's Bild. The mayor was known for voluntarily taking in more asylum-seekers than the small town was obliged to.